Pen



FIG. 1 is a front right perspective view of a pen showing my new design.

FIG. 2 is a rear elevation view thereof.

FIG. 3 is a front elevation view thereof.

FIG. 4 is a right side elevation view thereof.

FIG. 5 is a left side elevation view thereof.

FIG. 6 is a top plan view thereof.

FIG. 7 is a bottom plan view thereof.

FIG. 8 is an enlarged top plan view thereof; and,

FIG. 9 is an enlarged bottom plan view thereof. 

CLAIM The ornamental design for a pen, as shown and described. 